1. Field of the Invention
The present invention pertains to a letter opener with a round knife.
2. Description of the Related Art
An extremely wide variety of letter openers which produce a waste strip while opening an envelope are known from the literature. In this regard, reference can be made merely by way of example to the device for opening envelopes described in CH-A-660,571. In openers of this type, waste is produced, which must be disposed of. In addition, the content of the envelope can also be cut when the envelope is slit open.
Devices are also known which open an envelope without producing any waste. In the machines described in U.S. Pat. No. 4,419,915 and in EP-A-703,097, the envelope is carried by transport devices (belts and similar means of conveyance) past a knife mounted permanently in a housing. Machine designs of this type are complicated and expensive. In addition, there is often the danger that, because of the cutting moment and the transport or braking forces acting at a different point on the letter, the letter can be rotated or upended during the cutting process.